Loudspeakers have been added to cellular and portable telephone handsets to allow for more than one person to listen to a telephone conversation and/or provide for “hands-free” (“speakerphone”) operation of the telephone handset. Unfortunately, when the loudspeaker (transducer) in the telephone handset is used to reproduce a human voice, the perceived loudness or volume of the voice may be too low for noisy environments (e.g., in a moving car) and, to compensate, a user may increase the volume control for the loudspeaker so much that the voice becomes distorted. The lack of loudness stems from the human voice having a low average-to-peak amplitude ratio (i.e., the peak amplitude of the voice signal is significantly greater than the average amplitude of the voice signal), the relatively small size of the loudspeaker (typically ˜1 cm. across), and/or the limited power capability of the amplifier driving the loudspeaker (e.g., to increase battery life).
One common approach to improve the perceived loudness of a voice signal from the loudspeaker is to compress and/or clip the audio signal prior to amplification to increase the average-to-peak amplitude ratio of the audio signal. However, the compression and clipping can increase the distortion of the voice signal from the loudspeaker, possibly reducing intelligibility.